Control device for the throughput in a conduit portion or similar

ABSTRACT

The present invention relates to control device for the throughput in a conduit portion, comprising a valve or a flap composed of a body mounted on a rotary support shaft and being displaceable between a position of maximum closure and a position of minimum closure by pivoting about said shaft. Device characterised in that at least one shape or structure ( 4, 4 ′) which is at least partially obstructive, projecting into the internal passage of said conduit portion ( 1 ) and locally reducing the passage section thereof, is present in the region of the internal face of the wall ( 1 ) of said conduit portion ( 1 ) and comprises at least one cooperating surface zone ( 5 ) which intimately mates with the shape of at least one part of the imaginary surface swept by at least one segment of the external peripheral edge ( 6 ) of the body ( 2 ) of the valve or flap when pivoted.

TECHNICAL FIELD

The present invention relates to the field of the control of the flow ofa liquid in a conduit, a pipe or similar and relates to a control devicefor the throughput in a conduit portion or similar.

BACKGROUND ART

Numerous embodiments of check valves or butterfly valves are alreadyknown in which the throughput is controlled by means of a discoidal bodyfitted in a conduit portion, and mounted on a rotary shaft, allowing itto be displaced by pivoting between a closed position in which ittotally blocks and obstructs the passage (a position which is generallyperpendicular to the flow direction) and an open position, perpendicularto the previous position and in which it opposes a minimum resistance tothe flow of liquid.

Such embodiments of valves or flaps are in particular described in theFrench patent application No. 00 02644 and in the patent application PCTNo. WO 01/16473 in the name of the Applicant.

However, in these known control devices, the evolution of the throughputas a function of the opening (in other words the pivoting) of the valvebody is always identical (substantially proportional), as the shape ofsaid body is inevitably adapted to the section of the conduit—to enableclosure thereof in the closing position.

However, in certain applications, it may be desirable to have anevolution which is different therefrom flowing from the variableinterstice formed between the rotary body and the internal face of thewall.

Thus in certain systems for controlling the throughput, when the flap isopened, the evolution of the liquid passage section can take place tooquickly for certain applications which need a wide useful range ofthroughput at the start of opening.

In this case it would be necessary to reconcile a flap with a largesection for large throughputs with full opening and a flap with a smallsection for small throughputs with a small opening.

DISCLOSURE OF INVENTION

The present invention relates in particular to overcoming theabove-mentioned limitations and providing, in particular a simplesolution in response to the above-mentioned aim.

For this purpose, the invention relates to a control device for thethroughput in a conduit portion or similar, comprising a valve or a flapcomposed of a body substantially of the plate type or similar mounted ona rotary support shaft and being displaceable between a position ofmaximum closure, possibly total closure, and a position of minimumclosure by pivoting about said shaft, characterised in that at least oneshape or structure which is at least partially obstructive, projectinginto the internal passage of said conduit portion and locally reducingthe passage section of the latter, is present in the region of theinternal face of the wall of said conduit portion and comprises at leastone cooperating surface zone which intimately mates with the shape of atleast one part of the imaginary surface swept by at least one segment ofthe external peripheral edge of the body of the valve or flap whenpivoted.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in more detail with the aid of thedescription hereinafter which relates to a preferred embodiment, givenby way of non-limiting example and described with reference to theattached schematic drawings, in which:

FIG. 1 is a longitudinal section of a control device according to anembodiment of the invention mounted in a conduit portion;

FIG. 2 is a view according to the arrow A (direction of flow ofcirculation) of the device shown in FIG. 1, and

FIG. 3 shows throughput curves at constant input pressure for a controldevice, respectively, such as is shown in FIGS. 1 and 2 (broken linecurve) and without obstructive shape or structure according to theinvention (solid line curve).

BEST MODE FOR CARRYING OUT THE INVENTION

FIGS. 1 and 2 of the attached drawing 4 therefore show a control devicefor the throughput in a conduit portion 1 or similar, comprising a valveor flap composed of a body 2, substantially of the plate type orsimilar, formed or rigidly mounted on a shaft 3 for support and rotationand displaceable between a maximum closure position, possibly completeclosure, and a minimum closure position by rotation about said shaft 3,the latter being rotated by an external member.

According to the invention, at least one shape or structure 4, 4′ whichis at least partially obstructive, projecting into the internal passageof said conduit portion 1 and locally reducing the passage section ofthe latter, is present in the region of the internal face of the wall 1′of said conduit portion 1 and comprises at least one cooperating surfacezone 5 which intimately mates with the shape of at least one part of theimaginary surface swept by at least one segment of the externalperipheral edge 6 of the body 2 of the valve or flap when pivoted.

According to a first characteristic of the invention the cooperatingsurface zone(s) 5 of said projecting obstructive shape or structure 4,4′ extends/extend from the zone 1″ of the internal face of the wall 1′of the conduit portion 1 in contact with the body 3 of the valve or flapin maximum closure position, and at most to the plane comprising, on theone hand, the rotary shaft 3, and on the other hand, the flow directionD or the longitudinal axis X of said conduit portion 1.

The passage section as seen by the liquid circulating in the conduitportion 1 will therefore be defined in cooperation with the body 2 andthe obstructive shape(s) or structures 4, 4′. Said section can easily bevisualised by projection onto a plane perpendicular to said flowdirection D.

By acting on the size, the configuration and the view of the obstructiveshape(s) or structure(s) 4, 4′, the evolution of the passage section andtherefore of the throughput as a function of the inclination of the body2 of the valve or flap can be modified or adapted to very variedprofiles, with progressions (continuous or otherwise), limitations, etc.

In a preferred manner, however, the configuration of the cooperatingsurface zone(s) 5 of each obstructive shape or structure 4, 4′, possiblysub-divided into several distinct regions, is such that the total lengthof the line or strip portion(s) of this zone or these zones which is orare in contact with the body 2 of the valve or flap for each positionthereof in a given angular range, decreases when said body 2 is pivotedfrom its position of maximum closure toward its position of minimumclosure.

Thus, each shape or structure 4, 4′ has an appearance which is taperedfrom its base (in the region of the internal face of the wall 1) towardsits peak (innermost end) and therefore the passage section increasesmore and more rapidly with the rotation of the body of the valve or flap2 towards its open position.

In order to keep a large passage section in a minimum closure positionof the body 2, while allowing fine control of the flow at the start ofopening of the valve or flap the cooperating surface zone(s) 5extends/extend, as viewed from the body 2 of the valve, over an angularrange of at most ₄₅° from the maximum closure position perpendicular tothe flow direction D or the longitudinal axis X of the conduit portion1.

According to an advantageous embodiment of the invention and as shown inFIG. 2 of the attached drawings each projecting obstructive shape 4, 4′has at least one cut-out, one indent 7 and/or one through passage in theflow direction D, opening in the region of the cooperating surface zone5 and in cooperation with the body 2 defining the passage section ofsaid conduit portion 1 in the region of the relevant valve or flap, whensaid body 2 of the valve or flap is in contact with the said shape 4,4′.

In order to also allow control in the immediate vicinity of its positionof total closure, at least one indent or cut-out 7 extends to theinternal face of the wall 1′ of the conduit portion(s).

Thus, immediately after detachment of the body of the valve 2 from itsposition of complete closure (perpendicular to the flow direction D inFIGS. 1 and 2), a passage section which is limited but not zero will bedefined, with the geometric characteristics perfectly determined.

According to a preferred embodiment, shown in FIGS. 1 and 2 of theattached drawings, said control device comprises two obstructive shapesor structures 4 and 4′ situated on either side of the plane containing,on the one hand, the flow direction D or the longitudinal axis X of theconduit portion 1 and, on the other hand, the shaft for support androtation 3 of the body 2 of the valve or flap, the one upstream and theother downstream of said rotary shaft 3.

The obstructive shapes and structures 4 and 4′ will have different typesof constitutions and exterior appearances such as, for example, a hollowor solid body, a simple wall portion or voluminal body, a profiled viewor otherwise, etc.

According to a particularly advantageous embodiment of the invention,shown in the figures of the attached drawings, each obstructive shape orstructure 4, 4′ has, as viewed in section in planes perpendicular to therotary shaft 3, an angular configuration with one side in the form ofthe arc of a circle corresponding to a or the cooperating surface zone5, said angle being directed upstream for the shape or structure 4located upstream of the rotary shaft 3 and directed upstream for theshape or structure 4′ located downstream from the rotary shaft 3.

Owing to a configuration of this type of the shapes or structures 4 and4′, the disturbance of the flow will be limited, in particular in theposition of maximum opening of the valve or flap.

Although shown in FIG. 2 with a single indent 7 in the form of a notchwith a triangular section, each shape or structure 4, 4′ can obviouslycomprise a plurality of indents of this type, optionally with differentshapes, sections and sizes.

According to a first construction variation, each obstructive shape orstructure 4, 4′ is connected on the internal face of the wall 1′ of theconduit portion 1, by mechanical fixing, adhesion or otherwise.

According to a second construction variation, each obstructive shape orstructure 4, 4′ is produced in one piece with the wall 1′ of the conduitportion 1, if necessary obtained by deformation of this wall 1′.

Moreover, the invention may apply to conduit portions 1 of varioussections, associated with valve or flap bodies 2 with correspondingshapes, in particular: rectangular, square, elliptical, or other.

However, in a conventional manner, the body 2 of the valve or flap willhave a circumferential discoidal configuration or circular peripheraledge 6, the cooperating surface zone(s) 5 of the obstructive shape(s) orstructure(s) 4, 4′ being supported by a sphere.

Thus, in most cases of application and as shown in the figures of thedrawings, the obstructive shapes 4 and 4′ form evolutional profiles witha spherical contact surface zone 5 resuming the curve of the body 2 ofthe flap.

The cooperating surface 5 is sufficiently close to the flap to havefriction contact therewith and to thus ensure sealing during opening ofthe flap. The shapes 4, 4′ are only active at the start of opening theflap (cf. FIG. 1).

In this case there is not always a passage section for the liquid. Thissection is created in the spherical form by a notch 7 (FIG. 2) of adimension such that the surface projected in the axis of the conduit isthe desired passage section at a given angle.

According to the shape of the notch the desired progressivity can beobtained.

FIG. 3 shows, in a comparative manner the evolution of the throughput asa function of the opening of the body 2 of the flap for a same conduitportion 1 with and under shapes 4, 4′ for a constant input pressure.

The invention is obviously not limited to the embodiment described andshown in the attached drawings. Modifications remain possible, inparticular from the point of view of the constitution of the variouselements or by substituting the equivalent techniques without in any waydeparting from the scope of protection of the invention.

1. Control device for the throughput in a conduit portion or similar,comprising a valve or a flap composed of a body substantially of theplate type or similar mounted on a rotary support shaft and beingdisplaceable between a position of maximum closure, possibly totalclosure, and a position of minimum closure by pivoting about said shaft,characterised in that at least one shape or structure (4, 4′) which isat least partially obstructive, projecting into the internal passage ofsaid conduit portion (1) and locally reducing the passage sectionthereof, is present in the region of the internal face of the wall (1′)of said conduit portion (1) and comprises at least one cooperatingsurface zone (5) which intimately mates with the shape of at least onepart of the imaginary surface swept by at least one segment of theexternal peripheral edge (6) of the body (2) of the valve or flap whenpivoted.
 2. Device according to claim 1, in that the cooperating surfacezone(s) (5) of said projecting obstructive shape or structure (4, 4′)extends/extend from the zone (1″) of the internal face of the wall (1′)of the conduit portion (1) in contact with the body (2) of the valve orflap in the maximum closure position, and at most to the planecomprising, on the one hand, the rotary shaft (3), and on the otherhand, the flow direction (D) or the longitudinal axis (X) of saidconduit portion (1).
 3. Device according to claim 1, characterized inthat the total length of the line or strip portion(s) of the cooperatingsurface zone(s) (5) of each projecting obstructive shape or structure(4, 4′) which is/are in contact with the body (2) of the valve or flapfor each position thereof in a given angular range, decreases when saidbody (2) is pivoted from its maximum closure position toward its minimumclosure position.
 4. Device according to claim 1, characterized in thatthe cooperating surface zone(s) (5) extends/extend, as viewed from thebody (2) of the valve, over an angular range of at most 45° from themaximum closure position perpendicular to the flow direction (D) or thelongitudinal axis (X) of the conduit portion (1).
 5. Device according toclaim 1, characterized in that each projecting obstructive shape (4, 4′)has at least one cut-out, one indent (7) and/or one through passage inthe flow direction (D), opening in the region of the cooperating surfacezone (5) and in cooperation with the body (2) defining the passagesection of said conduit portion (1) in the region of the relevant valveor flap, when said body (2) of the valve or flap is in contact with thesaid shape (4, 4′).
 6. Device according to claim 5, characterized inthat at least one indent or one cut-out (7) extends to the internal faceof the wall (1′) of the conduit portion(s).
 7. Device according to claim2, characterized in that it comprises two obstructive shapes orstructures (4 and 4′) situated on either side of the place containing,on the one hand, the flow direction (D) or the longitudinal axis (X) ofthe conduit portion (1) and, on the other hand, the shaft for supportand rotation (3) of the body (2) of the valve or flap, the one upstreamand the other downstream of said rotary shaft (3).
 8. Device accordingto claim 2, characterized in that each obstructive shape or structure(4, 4′) as viewed in section in planes perpendicular to the rotary shaft(3), has an angular configuration with one side in the form of the arcof a circle corresponding to a or the cooperating surface zone (5), saidangle being directed upstream for the shape or structure (4) locatedupstream of the rotary shaft (3) and directed upstream for the shape orstructure (4′) located downstream from the rotary shaft (3).
 9. Deviceaccording to claim 1, characterized in that each obstructive shape orstructure (4, 4′) is connected on the internal face of the wall (1′) ofthe conduit portion (1).
 10. Device according to claim 1, characterizedin that each obstructive shape or structure (4, 4′) is produced in asingle piece with the wall (1′) of the conduit portion (1), if necessaryobtained by deforming this wall (1′).
 11. Device according to claim 1,characterized in that the body (2) of the valve or flap has acircumferential discoidal configuration or circular peripheral edge (6),the cooperating surface zone(s) (5) of the obstructive shape(s) orstructure(s) (4,4′) being supported by a sphere.